Regarding a thermal power plant and the like, methods have been studied to separate and capture carbon dioxide from a combustion exhaust gas by bringing the combustion exhaust gas into contact with an amine-based absorbing liquid to store the captured carbon dioxide without being released to the air.
Specifically, a carbon dioxide capturing system is known which includes an absorber that causes an absorbing liquid to absorb carbon dioxide contained in a combustion exhaust gas and discharges the absorbing liquid having absorbed the carbon dioxide (rich liquid), and a regenerator that heats the rich liquid discharged from the absorber and causes the rich liquid to release a carbon dioxide gas to regenerate the absorbing liquid. The regenerator is connected to a reboiler to supply a heat source to the regenerator. The absorbing liquid regenerated in the regenerator (lean liquid) is fed to the absorber, so that the absorbing liquid is circulated in the system.